This invention relates to the manufacture of injection laser packages, and in particular to the manufacture of hermetically sealed injection laser packages with glass optical fiber tails especially, though not exclusively, for use in submarine telecommunications cable. For submarine telecommunications use the fiber will normally be single mode fiber, and single mode fiber will also be the preferred option for many landline applications.
An important characteristic for any component destined for submarine use in a telecommunications cable is that it shall operate reliably without need for servicing for a period typically exceeding 25 years. In the context of the present device, this means that a construction is required which will provide long term hermeticity of the package and stability of the position of the inner end of the optical fiber tail with respect to the laser.